Developers have long requested direct access to driving directions data from Google. Now they've got it, Google announced so today at its I/O conference (our Google Directions API profile). The feature comes after MapQuest who became the first major player to offer its directions as a Web Service for free.
However, the Google Maps API terms of service restrict complete freedom. Section 10.12 forbids the "use or display the Content without a corresponding Google map." In other words, you can't put the driving directions on a Yahoo Map, nor can you store the results of bulk lookups. Both are reasonable restrictions that shouldn't hamper most developers.
While MapQuest may have beat Google to launching a web service, it's been on the search giant's radar for some time. It's been over two years since the feature was added to the public issue tracker for the Google Maps API. We'll be very interested to see the creative and useful ways developers put this valuable new capability to use.